Various types of guards for rotary cutting tools, such as angle grinder, are disclosed in the prior art. These guards typically cover a portion of the cutting blade or disc of the tool, thereby  protecting the user from accidentally contacting the blade or disc of the cutting tool with any part of the body, such as the hands. Such guards further reduce the likelihood that flying debris created during the cutting process will be flung directly back into the user's face or eyes.
When cutting workpieces having a 360° circumference, such as pipes, it is common to use tools such as angle grinders, which are capable of cutting through metal, PVC, and other materials commonly used for constructing pipe. To cut through the entire circumference of a pipe, it is necessary to access the entire exterior surface of the pipe. However, guards currently in use for rotary cutting tools, such as angle grinders, are often fixed in place relative to the cutting blade or disc, or at best can be manually adjusted along a limited range of travel. Accordingly, the user must alter the angle at which the cutting tool is held or move to the opposite side of the pipe being cut. If the opposite side of the pipe is not accessible, the user is forced to stop and adjust the positioning of the guard relative to the cutting blade or disc to complete the cutting process. Often, the user's solution is to remove the guard, thereby increasing the risk of injury.
It is therefore a paramount object of the present invention to provide a guard for a rotary cutting tool which allows for automatic adjustment of the guard relative to a workpiece.
It is a further object of the present invention to provide a guard that allows a user to cut, grind, or brush around substantially the entire circumference of a round workpiece, such as a pipe, without requiring alteration of the angle at which the tool is held, repositioning by the user, or repositioning or removal of the guard.
These and other objects and advantages of the present invention will become apparent upon a reading of the following description along with the appended drawings. 